The beginning of a new year is always a cause for kissing. Mad Men features plenty of that particular activity. If you need a refresher, here is a random sampling of memorable Mad Men kisses to get you in a Mad Men frame of mind for 2012. Remember a kiss that isn't listed here? Share it in the comments section below.

Don and Rachel Menken in Season 1, Episode 3, "Marriage of Figaro"With the Manhattan skyline as a backdrop, Don and Rachel share their first kiss on the Menken's rooftop. As a bonus, Rachel gets a doggie kiss from one of her German Shepherds.

Pete and Peggy in Season 1, Episode 8, "The Hobo Code"Pete and Peggy arrive early for work at Sterling Cooper, which provides a perfect opportunity for whispered confessions and a morning tryst.

Sal and Joan in Season 1, Episode 12, "Nixon vs. Kennedy"Sal and Joan kiss while performing a reading of Paul's play at Sterling Cooper's election party. Afterward, Sal basks in the whistles and cheers while Joan casts her eyes downward.

Harry and Hildy in Season 1, Episode 12, "Nixon vs. Kennedy"Nixon takes Ohio, prompting Harry to give Hildy a celebratory smooch at the office party. One thing leads to another and the two end up spending the night together in his office.

Don and Betty in Season 1, Episode 13, "The Wheel"Betty and Don welcome 1956 with an embrace -- an image Don includes in his pitch for the Carousel slide projector, a device that brings people "to a place where we know we are loved."

Sal and the Bellhop in Season 3, Episode 1, "Out of Town"Sal's on a business trip and doesn't resist when a bellhop removes his own shirt, undoes Sal's belt and zipper and starts to go even further -- until a fire alarm spoils the fun.

Don and Betty in Season 3, Episode 8, "Souvenir"It's Rome, and Betty's wanted by locals and Don alike. In their hotel room, Don nuzzles Betty's neck and undresses her as she stands with her back to him.

Don and Betty in Season 3, Episode 12, "The Grown Ups"Betty and Don dance at Margaret Sterling's wedding and kiss deeply on the dance floor. The next day, Betty reveals to Don that "I kissed you yesterday. I didn't feel a thing."

Allison and Don in Season 4, Episode 2, "Christmas Comes But Once a Year"Don, drunk, asks Allison to tend to him. As she leaves, he takes her hand and pulls her onto his lap for a kiss. She tries to resist but gives in to his advances. "I feel dizzy," she says.

Peggy and Abe in Season 4, Episode 4, "The Rejected"During a police raid, Peggy finds herself nestled in a closet with Abe. "I feel like I should kiss you," he says. Peggy leans in and he does, just as they're interrupted by Joyce.

Roger and Joan in Season 4, Episode 9, "The Beautiful Girls"A mugger holds up Roger and Joan on the street, prompting a shaken Joan to kiss Roger, imploring him, "Don't stop." The next day, Roger tells her, "I feel something. And I know you do."